Flexible packaging structure with built-in tamper-evidence features and method for making same

ABSTRACT

A flexible packaging laminate has built-in opening/reclose and tam per-evidence features by forming the laminate from an outer structure joined in face-to-face relation to an inner structure. Score lines are formed in both structures to enable an opening to be formed through the laminate by lifting a flap or the like out of the plane of the laminate. The score line through the outer structure defines a larger opening than the score line through the inner structure, such that a marginal region of the outer structure extends beyond the edge of the opening portion of the inner structure. A pressure-sensitive adhesive is used to re-adhere the marginal region to an underlying surface of the inner structure adjacent the opening through the laminate. The outer score line includes at least one tear portion that is torn through upon initial opening, thus indicating the package has been at least partially opened.

CROSS-REFERENCE TO A RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.15/974,055 filed May 8, 2018, which is a continuation of U.S. patentapplication Ser. No. 13/668,947, filed Nov. 5, 2012, which is acontinuation of U.S. patent application Ser. No. 12/043,442, filed Mar.6, 2008, each of which are incorporated herein in their entirety byreference.

BACKGROUND OF THE INVENTION

This disclosure relates to product packaging formed in whole or in partby a flexible film, in which the film has a score line that defines aflap that can be lifted to create an opening through the film to gainaccess to the product, and wherein the flap can be reattached to theremainder of the film to close the opening.

A variety of food and non-food products are packaged using flexiblepackaging materials formed primarily of laminations of one or more ofpolymer films, metallized polymer films, paper, metal foil, and thelike. In many instances, packages contain products that may be used orconsumed a little at a time, and the products may be susceptible tobeing adversely affected (e.g., becoming soggy, drying out, etc.) byexposure to the surrounding environment. Accordingly, there isfrequently a desire to be able to reclose a package after its initialopening to keep product that remains in the package fresh.

Various opening and reclose arrangements have been developed forflexible packaging, for example as disclosed in U.S. patent applicationSer. No. 11/098,872 (“the '872 Applications”), filed on Apr. 5, 2005,incorporated herein by reference. Often, reclosability is achieved byusing a pressure-sensitive adhesive label that is attached to theexterior of the package adjacent the location where the package isopened. Such labels are formed separately from the packaging structureitself and are added to the packaging structure. Thus, the labels thusrepresent additional expense. Furthermore, it is often necessary to shipa roll of the packaging material to a converter for application of thelabels, after which the roll is shipped back to the packager formanufacture of the packages. This manufacturing process is inefficient.The use of labels also entails waste in that it is typically necessaryto employ a release liner with the labels, which liner is removed anddiscarded. The labels are usually die cut from a web of material, andthe skeleton left over after the die-cutting operation is also wasted.

Because of the drawbacks of using labels as noted above, the assignee ofthe present application has developed a flexible packaging structurewith a built-in opening and reclose feature, as described in theaforementioned '872 application. Packages made using the flexiblepackaging structure of the '872 application avoid the disadvantagesassociated with the use of labels, and have additional advantages.

Consumers feel more confident about purchasing such types of packages ifthe packages have a tamper-evidence capability so that the consumer canreadily see whether the package has already been opened. Presently,various flexible packages have features allowing a user to determine ifa package has already been opened or tampered with. Unfortunately, thetamper-evidence features of such packages may be difficult to discernupon a visual inspection of the package. Further, such temper-evidencefeatures often require removing a portion of the packaging, and thus,creating unwanted trash and potential choking hazards. The presentdisclosure is directed toward providing improved tamper-evidencecapabilities.

BRIEF SUMMARY OF THE DISCLOSURE

The present disclosure addresses the above needs and achieves otheradvantages, by providing a flexible packaging structure and method formaking same, in which the structure has opening/reclose andtamper-evidence features built into the structure. In accordance withone embodiment of the invention, the score line or die cut through thefilm for creating the flap includes one or more tear portions in whichthe flap includes a tab with an end attached to the structure, and/or aninterrupted area of the flap that is not cut. When the flap is peeledback, a portion of the tab or the film in the interrupted area is torn.The tab can include an indentation and/or a prong, while the interruptedarea can be formed by a transverse cut that is U-shaped or V-shaped toensure that the tear will connect with the die cut. The presence of atear or slit in the tab or the interrupted area indicates that thepackage has already been opened or tampered with.

In some embodiments, the package itself is formed to have a built-inopening and reclose feature by forming the packaging structure as atwo-part structure, having an outer structure joined in face-to-facerelation with an inner structure. Each of the outer and inner structurescan comprise one or more layers of flexible packaging material such aspolymer film, paper, metal foil, and the like. An outer line of weaknessis formed in the outer structure to define an outer opening portion thatcan be lifted out of the plane of the outer structure. Similarly, aninner line of weakness is formed in the inner structure to define aninner opening portion that can be lifted out of the plane of the innerstructure. The outer and inner opening portions are attached to eachother such that the outer and inner opening portions can be lifted outof the plane as a unit, thereby creating an opening through thepackaging structure defined by the inner line of weakness. The outerline of weakness includes a tear portion whose torn or untorn conditionis readily apparent from a visual inspection of the outer structure.

The outer opening portion is larger in area than the inner openingportion and has a marginal region that extends beyond the peripheraledge of the inner opening portion. When the outer and inner openingportions are lifted out of the plane to create the opening, anunderlying portion of the inner structure in registration with themarginal region of the outer opening portion is exposed adjacent theopening. A pressure-sensitive adhesive is applied to either the marginalregion of the outer opening portion or the underlying portion of theinner structure. Therefore, after initial lifting of the outer and inneropening portions, the opening through the structure can be reclosed byadhering the marginal region of the outer opening portion to theunderlying portion of the inner structure via the pressure-sensitiveadhesive.

In accordance with one embodiment, the pressure-sensitive adhesive ispattern-applied onto one surface of the outer structure, thepressure-sensitive adhesive forming a strip having an outer perimeterand an inner perimeter, and a permanent laminating adhesive ispattern-applied onto the one surface of the outer structure such thatthe permanent adhesive does not cover the strip of pressure-sensitiveadhesive. Next, the outer structure is adhesively joined to the innerstructure via the permanent adhesive so as to form a laminate. The outerstructure and inner structure in preferred embodiments are coextensivewith each other, and advantageously are each continuous webs drawn fromrespective supply rolls and laminated together to form a laminate thatis a continuous web.

The laminate is then advanced to a scoring station at which an outerline of weakness (also referred to herein as a “score line”) is formedthrough the thickness of the outer structure, and an inner score line isformed through the thickness of the inner structure. Advantageously,each of the score lines is registered with respect to the strip ofpressure-sensitive adhesive such that neither score line is locatedwhere there is permanent laminating adhesive between the outer and innerstructures. The outer score line delineates the outer opening portion ofthe outer structure that is separable from the outer structure along theouter score line, and the inner score line delineates the inner openingportion of the inner structure that is affixed to the outer openingportion by the permanent adhesive and is separable from the innerstructure along the inner score line. The outer score line includes theinterrupted area.

The score lines can be formed by laser scoring or by mechanical scoringor cutting such as by die cutting or kiss cutting or the like. Theadhesive(s) can be applied to the outer structure as noted, butalternatively can be applied to the inner structure. The adhesive(s) canbe applied using any suitable equipment and technique, such as by agravure roll or the like.

The pressure-sensitive adhesive can be applied such that there is aregion that is free of the adhesive, such as a tab, to form a graspingportion of the opening portion that can be readily grasped and pulledback to initiate opening.

The outer line of weakness or score line preferably penetrates throughthe thickness of the outer structure but not through the innerstructure. Similarly, the inner score line preferably penetrates throughthe thickness of the inner structure but not through the outerstructure.

The inner structure of the laminate advantageously includes a sealantlayer forming the inner surface of the laminate. The sealant layer cancomprise a heat seal material such as polyethylene, polypropylene,ionomer resin such as SURLYN®, or the like, or a cold seal material. Theheat seal or cold seal layer can comprise either a film or a coating.The inner structure advantageously also includes a barrier layerproviding a barrier against the passage of moisture and/or oxygen. Insome applications such as the packaging of moisture-sensitive products(e.g., cookies or similar products that tend to be degraded when exposedto the environment), it is important to provide a moisture barrier. Thebarrier layer can comprise any of various polymer-based barriermaterials including barrier polymer films such as ethylene vinyl alcoholcopolymer (EVOH), polyamide, and the like; metallized polyolefin filmssuch as polyethylene, polypropylene, oriented polypropylene, and thelike; AlOx-coated polymer films; SiOx-coated polymer films; metal foilsuch as aluminum foil; and others. Although the term “barrier layer” isused in connection with metallized films to refer to the entiremetallized film, it will be recognized that it is the layer of metalthat provides the barrier function. Likewise, it is the AlOx or SiOxcoating that provides the barrier function in the ceramic-coated films,but the entire film nevertheless is referred to herein as a “barrierlayer”.

The outer structure advantageously includes a layer of polyester such aspolyethylene terephthalate, which has a desirable crisp feel and isreadily printed. The polyester layer can be printed with inks to providegraphics and indicia. In preferred embodiments, the polyester layer istransparent and is reverse-printed on the surface that faces the innerstructure.

The process in accordance with the present disclosure comprises anin-line process wherein the opening and reclose features and the tamper-evidence feature are formed in the packaging laminate during theproduction of the laminate. Accordingly, it is not necessary to ship thelaminate to a converter for application of labels or the like. Thus, thewaste and the various material and shipping expenses associated with theuse of separate labels are avoided.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Having thus described the disclosure in general terms, reference willnow be made to the accompanying drawings, which are not necessarilydrawn to scale, and wherein:

FIG. 1 is a diagrammatic depiction of a first phase of a manufacturingmethod for making a flexible packaging structure in accordance with oneembodiment of the invention;

FIG. 1a is a view of the first structure along line 1 a-1 a in FIG. 1;

FIG. 1b is a view of the first structure along line 1 b-1 b in FIG. 1;

FIG. 2 is a diagrammatic depiction of a second phase of the method inaccordance with one embodiment of the invention;

FIG. 3 is a diagrammatic depiction of a second phase of the method inaccordance with another embodiment of the invention;

FIG. 4 is a perspective view of a package that can be formed from aflexible packaging structure made in accordance with embodiments of theinvention;

FIG. 5 shows the package of FIG. 4 after being opened;

FIG. 6 is a cross-sectional view along line 6-6 in FIG. 4;

FIG. 7 is a cross-sectional view along line 7-7 in FIG. 5;

FIG. 8 is a perspective view of stand-up pouch that can be formed from aflexible packaging structure with a tamper-evidence feature made inaccordance with embodiments of the invention;

FIG. 9 is a perspective view of another stand-up pouch that can beformed from a flexible packaging structure with a tamper-evidencefeature made in accordance with embodiments of the invention;

FIG. 10 is a perspective view of yet another stand-up pouch that can beformed from a flexible packaging structure with a tamper-evidencefeature made in accordance with embodiments of the invention;

FIG. 11 is a perspective view of an additional stand-up pouch that canbe formed from a flexible packaging structure with a tamper-evidencefeature made in accordance with embodiments of the invention; and

FIG. 12 shows a perspective view of a package with a container body andhaving a temper-evidence feature in accordance with the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

The present inventions now will be described more fully hereinafter withreference to the accompanying drawings, in which some but not allembodiments of the invention are shown. Indeed, these inventions may beembodied in many different forms and should not be construed as limitedto the embodiments set forth herein; rather, these embodiments areprovided so that this disclosure will satisfy applicable legalrequirements. Like numbers refer to like elements throughout.

As an initial overview of preferred embodiments of the invention, aflexible packaging laminate is constructed to have a built-in openingand reclose function and a tamper-evidence feature. The laminate isconstructed as a multi-layer structure by adhesively laminating a firststructure to a second structure, wherein each of the first and secondstructures comprise one or more layers of flexible material.Pressure-sensitive adhesive is applied to one of the structures beforelamination. Once the laminate is formed in this manner, scoringoperations are performed on both sides of the laminate, but each scoringoperation penetrates only through a part of the thickness of thelaminate; in particular, a scoring operation performed on the side ofthe laminate adjacent the first structure results in penetration throughthe first structure, but without complete penetration through the secondstructure, and preferably without any substantial penetration, and morepreferably without any penetration, into the second structure. Likewise,the scoring operation performed on the side of the laminate adjacent thesecond structure results in penetration through the second structure,but without complete penetration through the first structure, andpreferably without any substantial penetration, and more preferablywithout any penetration, into the first structure. The scoring operationalso forms the tamper-evidence feature, as further described below.

More particularly, with reference to FIG. 1, a first phase of themanufacturing process is depicted. A first structure 10 is advanced froma supply roll 12 by suitable web driving and handling equipment (notshown) to an optional print station 14 comprising a printing apparatus,such as a rotogravure printer or the like, for printing graphics and/orindicia on the first structure by applying inks to a surface of thefirst structure. The first structure 10 comprises one or more layers offlexible packaging material. Various materials can be used for thelayer(s) of the first structure, including polymers such polyesters,polyolefins (including homopolymers and copolymers), polyamides, andothers; paper; metal foil; and the like. In a preferred embodiment ofthe invention, the first structure 10 includes an outer layer (notillustrated) that is substantially transparent and is reverse-printed inthe print station 14, i.e., the inks are applied to the surface of thefirst structure 10 that is subsequently laminated to another structure,as described below, from the opposite side of the first structure, whichwill form an exterior of a package constructed from the packaginglaminate, the inks are visible through the first structure. As anexample, the first structure 10 can comprise a layer of polyester suchas polyethylene terephthalate or the like.

Prior to printing the first structure in the print station, the surfaceof the first structure that is subsequently laminated to the otherstructure can be treated by a corona discharge or flame treatmentapparatus 16 to render the surface more receptive to the inks and/or torender the surface more readily bondable to the pressure-sensitiveadhesive that is subsequently applied to the surface as described below.Alternatively, the first structure 10 can have already been so treatedprior to being wound into the supply roll 12, such that the treatmentapparatus 16 is unnecessary.

Following the optional corona/flame treatment and/or optional printingoperation, and with reference to FIGS. 1 and 1 a, the first structure 10is advanced to a first adhesive application station 18 at which apressure-sensitive adhesive 20 is applied to the first structure in apredetermined pattern 22 that recurs at regular intervals along thelengthwise direction of the first structure. The predetermined pattern22 is generally in the form of a strip of various forms or shapes. Asillustrated, a preferred shape for the strip pattern 22 is generallyU-shaped, for reasons that will become apparent in the description ofFIGS. 4-8; however, other shapes for the pattern 22 can be used, theinvention not being limited to any particular pattern. The pattern caninclude a region 23 that is free of adhesive and will ultimately form athumb tab or grasping portion of the first structure 10 as furtherdescribed below. It is also possible in alternative embodiments toflood-coat the pressure-sensitive adhesive onto the entire surface ofthe first structure.

The pressure-sensitive adhesive 20 can comprise various compositions.Pressure-sensitive adhesives form viscoelastic bonds that areaggressively and permanently tacky, adhere without the need of more thana finger or hand pressure, and require no activation by water, solventor heat. Pressure-sensitive adhesives are often based on non-crosslinkedrubber adhesives in a latex emulsion or solvent-borne form, or cancomprise acrylic and methacrylate adhesives, styrene copolymers(SIS/SBS), and silicones. Acrylic adhesives are known for excellentenvironmental resistance and fast-setting time when compared with otherresin systems. Acrylic pressure-sensitive adhesives often use anacrylate system. Natural rubber, synthetic rubber or elastomer sealantsand adhesives can be based on a variety of systems such as silicone,polyurethane, chloroprene, butyl, polybutadiene, isoprene, or neoprene.When the packaging laminate of the invention is to be used for foodpackaging, the pressure-sensitive adhesive 20 generally must be afood-grade composition. Various pressure-sensitive adhesives areapproved by the U.S. Food and Drug Administration for use in direct foodcontact, as regulated by 21 CFR Part 175.300. A preferred food-gradepressure-sensitive adhesive 20 for use in the present invention isJonbond 743 available from Bostik Findley. Additives (e.g., particulatesor the like) can be added to the pressure-sensitive adhesive 20 toreduce the tenacity of the bond to the underlying second structure 42,if necessary, so that the pressure-sensitive adhesive 20 readilydetaches from the second structure on opening (particularly on the veryfirst opening).

When applied in a pattern as opposed to being flood-coated or appliedeverywhere on the first structure 10, the pattern 22 ofpressure-sensitive adhesive 20 is applied to the first structure 10 atregular intervals along the first structure 10. The spacing or indexdistance d between the patterns 22 can correspond to a dimension, suchas a length, of packages to be produced from the packaging laminate.

The adhesive application station 18 can comprise any suitable devicecapable of accurately applying the pressure-sensitive adhesive 20 to thefirst structure 10 in the desired pattern 22, at regular intervals alongthe structure. For example, as shown, the adhesive application stationcan comprise a gravure roll 24 that picks up the pressure-sensitiveadhesive 20 from a reservoir 26 on the outer surface of the roll suchthat the adhesive fills one or more recessed areas in the surface. Adoctor blade 28 scrapes off excess adhesive so that it remainsessentially only in the recessed area(s). The first structure 10 iscontacted by the gravure roll 24; a backing roll 30 provides support onthe opposite side of the first structure 10.

After application of the pressure-sensitive adhesive 20, the firststructure 10 is advanced to a dryer 31 such as an oven or the like, todry the pressure-sensitive adhesive 20. In the case of thepressure-sensitive adhesive 20 being pattern-applied, the firststructure 10 is then advanced to a second adhesive application station32 at which a permanent laminating adhesive 34 (FIG. 1b ) is applied tothe first structure 10 in such a manner that a sufficiently largeproportion of the surface is covered by the permanent adhesive 34 topermit the first structure 10 to be adhesively attached to a secondstructure 42 at a downstream laminating station 40. The permanentadhesive 34 does not cover the pressure-sensitive adhesive 20.Furthermore, when the pattern of pressure-sensitive adhesive 20 includesan adhesive-free region to form a thumb tab or grasping portion 23 aspreviously noted, the pattern of the permanent adhesive also does notcover the adhesive-free region. Thus, the permanent adhesive 34 must beapplied by an apparatus capable of accurately applying the adhesive in apredetermined pattern, in registration with the pressure-sensitiveadhesive 20 but not covering it or the adhesive-free region if present.A suitable adhesive application device 32, as shown, can be a gravureroll 24 of the type previously described. The permanent adhesive 34 cancomprise various compositions. Suitable examples include two-componentpolyurethane adhesive systems, such as Tycel 7900/7283 available fromHenkel. After the application of the permanent adhesive 34, the firststructure 10 is advanced to a dryer 33 such as an oven or the like.Alternatively, when the pressure-sensitive adhesive 20 is applied to theentire surface of the first structure 10, the steps of applying anddrying the permanent adhesive 34 are skipped.

The first structure 10 is then advanced to a laminating station 40,comprising a pair of rolls forming a nip therebetween. The firststructure 10 is passed through the nip along with a second structure 42that is advanced from its own supply roll 44, and the first and secondstructures 10/42 are laminated to each other. The second structure 42comprises one or more layers of flexible material, and is coextensivewith the first structure 10—i.e., the width of the second structure 42is substantially equal to the width of the first structure 10 and thelongitudinal edges of the second structure 42 substantially coincidewith the longitudinal edges of the first structure 10. The resultinglaminate 46 is then advanced to a reel-up (not shown) where it is woundinto a roll for subsequent processing in the second phase of themanufacturing process as described below. Alternatively, it is possiblefor the reel-up operation to be omitted, such that the laminate isdirectly advanced to the second phase.

With reference to FIGS. 2 and 6, the second phase of the process is nowdescribed. A supply roll 48 of the laminate 46 formed in the first phaseof the process is shown. The laminate is advanced from the supply rollto a first scoring station 50 at which a first, or outer, score line 52(FIG. 6) is formed through the thickness of the first structure 10. Whenthe pressure-sensitive adhesive 20 has been pattern-applied, the firstscore line 52 is in registration with (i.e., coincides with) the outerperimeter 22 a (FIG. 1a ) of the strip-shaped pattern 22 ofpressure-sensitive adhesive 20. The first score line 52 extendssubstantially through the thickness of the first structure 10, butpreferably does not extend to any substantial extent into the secondstructure 42, as illustrated in FIG. 6.

The first scoring station 50 can comprise a laser 54 as depicted in FIG.2. The use of lasers for scoring through flexible materials is generallyknown, for example as described in U.S. Pat. No. 5,158,499, incorporatedherein by reference. The depth of the score line formed by the laser canbe regulated by regulating the power output or beam intensity of thelaser beam, the width or spot size of the laser beam, and the amount oftime a given spot on the film surface is irradiated by the beam. Thesefactors generally are selected based on the characteristics of thematerial being scored. Some materials are more readily scored by lasersthan other materials, as known in the art.

As noted, the first score line 52 must be in registration with the outerperimeter 22 a of the pressure-sensitive adhesive strip 20 (and theouter perimeter of the thumb tab 23, if present). To accomplish thisregistration, the operation of the laser 54 is controlled to besynchronized with the advancement of the laminate 46. A sensor 56disposed adjacent the laminate 46 can be used for detecting a feature onthe laminate whose location in relation to the strip ofpressure-sensitive adhesive 20 is known, and the sensor's output signalcan be used by a suitable controller (not shown) for controlling thelaser 54.

The first score line 52 may also include one or more tear portions 65 asa tamper-evidence feature. A tear portion 65 may comprise one or moreinterrupted areas 57 in which the first structure 10 is not cut orscored, and whose uncut condition is readily apparent from a visualinspection of the first structure 10. The interrupted areas 57 arelocated such that when the flap or outer opening portion 86 bounded bythe first score line 52 is peeled back to create an opening through thelaminate, the first structure 10 tears through the interrupted areas 57to connect the two portions of the first score line 52 on opposite sidesof each interrupted area 57. To help ensure that the two portions of thescore line will be connected even if the tear line tends to wander indirection, the score line 52 at the “downstream” side of eachinterrupted area 57 can terminate in a U- or V-shaped portion 58 thatextends generally transverse to the direction along which the score line52 extends. The “downstream” side refers to the side of the interruptedarea 57 that is located farthest along the downstream direction(generally left-to-right in FIGS. 4 and 5) in which the outer openingportion 86 is peeled back when opening the package. The first structure10 is cut through its thickness along the transverse portions 58,similar to the rest of the score line 52. Accordingly, even if the tearline wanders to one side or the other, it will connect with thetransverse portion 58 and thereby allow the score line 52 to continue tosever or separate as the outer opening portion 86 is peeled fartherback.

Next, the laminate is advanced to a second scoring station 60 at which asecond, or inner, score line 62 is formed through the thickness of thesecond structure 42. When the pressure-sensitive adhesive 20 has beenpattern-applied, the second score line 62 is in registration with (i.e.,coincides with) the inner perimeter 22 b (FIG. 1a ) of the strip-shapedpattern 22 of pressure-sensitive adhesive 20. The second score line 62extends substantially through the thickness of the second structure 42,but preferably does not extend to any substantial extent into the firststructure 10, as illustrated in FIG. 6. The second score line 62 isspaced inwardly of the first score line 52 so as to define an inneropening portion 88 of smaller area than the outer opening portion 86. Asfurther described below, the inner opening portion 88 is adhered to theouter opening portion 86 (either by the permanent adhesive when present,or by the pressure-sensitive adhesive 20 when it is applied everywherebetween the two structures 10, 42), such that both portions 86, 88 arelifted together when opening the package.

As shown in FIGS. 4 and 5, preferably the interrupted areas 57 arelocated with respect to the second score line 62 such that in order tolift the outer opening portion 86 far enough to just begin lifting theinner opening portion 88 and thereby begin to create an opening into thepackage, the interrupted areas 57 must be torn through. In this regard,the downstream side of each interrupted area 57 (which coincides withthe vertex of the U- or V-shaped transverse score line 58) preferably isnot farther along the downstream direction, or at least is notsubstantially farther along the downstream direction, than is themost-upstream portion of the second score line 62.

The second scoring station 60 can comprise a laser 64. The operation ofthe laser 64 is synchronized with the advancement of the laminate in amanner as described above. A sensor 66 can detect a feature, such as aneye mark, on the laminate whose location in relation to thepressure-sensitive adhesive strip 20 is known, and the sensor 66 outputcan be used for regulating the laser operation so that the second scoreline 62 is in registration with the inner perimeter of thepressure-sensitive adhesive strip 20.

As an alternative to the use of lasers for scoring the laminate, thescore lines 52, 62 can be formed in the laminate by mechanical scoringor cutting. For instance, as depicted in FIG. 3, a first scoring station50′ can comprise a kiss roll 51 and backing roll 53 that form a nipthrough which the laminate is passed. The kiss roll 51 comprises arotary cutting die defining a cutting edge (not shown). The kiss rollacts in conjunction with the backing roll to cut partially through thethickness of the laminate starting from the outer surface of the firststructure 10, such that the first structure 10 is substantially scoredthrough while the second structure 42 is left intact. The second scoringstation 60′ likewise comprises a kiss roll 61 and backing roll 63 forscoring through the second structure 42.

Additionally, it is within the scope of the invention to laser-score oneside of the laminate and to kiss cut or otherwise mechanically score theother side. This can be advantageous, for example, when one of thestructures making up the laminate is readily scored by a laser but theother structure is not. For instance, when the first structure 10 is apolyester such as PET, it can readily be scored with a laser, but if apolyethylene heat seal layer is employed on the opposite side, laserscoring may not be the best choice because polyethylene does not scorewell with a laser. In this case, kiss cutting or other mechanicalscoring can be used to score the inner structure 42.

After the scoring operations, the laminate 46 can be sent to a reel-up(not shown) and wound into a roll for subsequent processing. Thelaminate can also be slit into a plurality of partial widths and woundinto multiple rolls. In this latter instance, each partial width wouldhave the recurring patterns of pressure-sensitive and permanentadhesives applied with suitably configured adhesive applicators to thefull-width material, and would have the recurring score lines formed bysuitably configured scoring devices acting on either the full-widthlaminate prior to slitting or acting on each partial-width portion afterslitting.

An advantage of the invention, versus the formation of a web havingdiscrete labels applied to a partial portion of the web surface as inthe prior art, is that the laminate has a uniform thickness throughout(because the first and second structures are coextensive) and thereforewinds well into good-quality rolls. In contrast, a web with labelscentrally located in the width of the web tends to produce wound rollsthat are soft in the radial direction at the two ends of the roll wherethe labels are not present. Additionally, the web with labels is muchthicker than laminates made in accordance with the invention, and hencethe laminates of the invention can achieve a greater square footage perroll of a given diameter. As already noted, a further drawback to theuse of labels is the necessity of applying the labels to the web in an“off-line” process, which often entails shipping a roll of the web to aconverter that applies the labels and then ships the roll back to thepackage manufacturer. In the process of the invention, the manufactureof the laminate and the incorporation of the opening/reclose andtamper-evidence features in the laminate are conducted in an in-linefashion as part of the same overall process. The process of theinvention thus is much more efficient and less costly.

Additionally, the invention avoids other drawbacks associated with theuse of labels. More specifically, pressure-sensitive adhesive labelstypically require a release liner that is peeled off and thrown away,which represents waste, and create a potential choke hazard.Furthermore, there is the additional waste of the skeleton material leftover after die-cutting the labels from the label web material. Thepresent invention eliminates such waste and attendant costs.

Some possible applications for the resulting laminate are now explainedwith reference to FIGS. 4-11. FIGS. 4 and 5 show a flexible package 70.The package includes an outer wrapper 74 that envelopes the packagecontents and is sealed to enclose the contents. The outer wrapper 74comprises a packaging laminate made by a method in accordance with theinvention, such as the laminate 46 previously described. The outerwrapper 74 is manipulated into a tubular shape and the longitudinaledges of the wrapper 74 are sealed together by a suitable sealantmaterial to form a longitudinal seal (not shown), typically adjacent thebottom surface of the package. The opposing portions of the wrapper 74are sealed together along transverse seal lines 76, 78 adjacent theopposite ends of the tubular wrapper. The ends of the wrapper 74 can begusseted if desired, as known in the art.

In the illustrated package, the portion of the outer wrapper 74 havingthe score lines 52, 62 is provided to be on the top surface of thepackage. The area of the wrapper 74 bounded by the score lines canconstitute any fraction of the total top surface of the package, butadvantageously the area is a majority of the total surface area of thetop surface.

Based on the previous description of the laminate 46 and its formationprocess, it will be appreciated that the presence of the score lines 52,62 has little or no impact on the barrier function of the outer wrapper74 because each score line extends only partially through the totalthickness of the wrapper 74 and the score lines are not aligned witheach other. Additionally, the pressure-sensitive adhesive 20 fills thespace between the score lines so that even if the score lines overlapsomewhat in the thickness direction, there is still no open routebetween them. Furthermore, the score lines typically have a small width,on the order of a few thousandths of an inch.

Various materials can be used for the construction of the outer wrapper74. With reference to FIG. 6, in the illustrated embodiment, the firststructure 10 that forms the outer surface of the wrapper 74 comprises asingle layer 80 of flexible material. The layer 80 can comprise variousmaterials. A preferred material is a polyester such as polyethyleneterephthalate (PET). As noted, the PET layer can be reverse-printed ifdesired, although alternatively it can be printed on its exterior andcovered by an over-lacquer (not shown). The second structure 42 formingthe inner surface of the wrapper 74 comprises a barrier layer 82 and asealant layer 84. The sealant layer 84 constitutes the innermost surfaceof the wrapper 74, and can comprise various sealant materials such asheat seals or cold seals. Heat seals generally are preferred becausethey provide stronger seals than cold seals typically are capable ofachieving. Any suitable heat seal materials can be employed, such aspolyethylene, polypropylene, ionomer resins such as SURLYN®, or others.

The barrier layer 82 can comprise any of various barrier materialsincluding barrier polymer films such as: ethylene vinyl alcoholcopolymer (EVOH), polyamide, and the like; metallized polyolefin filmssuch as polyethylene, polypropylene, oriented polypropylene, and thelike; AlOx-coated polymer films; SiOx-coated polymer films; metal foil;and others.

The barrier layer 82 and sealant layer 84 can be joined in various ways,including adhesive lamination, extrusion lamination, or coextrusion.

Advantageously, the laminate includes a metallization layer or a metalfoil layer between the first structure 10 and the second structure 42,for example by providing a metallization layer 85 on the surface of thelayer 82 that faces the first structure 10. This is beneficial inenhancing the barrier performance of the laminate as already noted.Additionally, however, the metallization layer or 85 metal foil layercan also be helpful when a laser is used for scoring the secondstructure 42. In particular, when the sealant layer 84 comprisespolyethylene, which is not as readily scored by laser as some othermaterials such as polyester, it can be difficult to employ asufficiently high laser energy to score through the polyethylene sealantlayer without scoring through the laminate more deeply than desired. Insome cases, the entire thickness of the laminate may be scored through,which is undesirable. The metallization layer or metal foil layer can behelpful in “tuning” the laser to penetrate only up to the metallizationlayer 85 or foil layer.

The function of the opening/reclose and tamper-evidence featuresprovided by the pattern-applied adhesives and the score lines will nowbe described. With reference to FIGS. 4 and 6, the package 70 is shownin a closed condition, for example as initially filled and sealed in apackaging plant. On the top surface of the outer wrapper 74, the firstor outer structure 10 is adhesively joined to the second or innerstructure 42 via the permanent adhesive 34. The first score line 52bounds an outer opening portion 86 of the outer structure 10. In thisembodiment, the outer opening portion 86 has a generally U-shapedperimeter having three sides defined by the score line 52, and isattached to the remainder of the outer wrapper 74 along a fourth side(i.e., an imaginary line extending between the free ends of the two legsof the U-shaped score line 52). The second score line 62 is generallyparallel to the first score line 52, but is spaced inwardly of the outerscore line so as to define an inner opening portion 88 of smaller areathan the outer opening portion 86; the second score line 62 can be aclosed curve such as a rectangle, or can be generally U-shaped like thefirst score line 52, as desired. In any event, there is a marginalregion 90 of the outer opening portion 86 that extends beyond the edgeof the inner opening portion 88. The pressure-sensitive adhesive 20 isdisposed between this marginal region 90 and an underlying surface 92 ofthe inner structure 42. The outer opening portion 86 and inner openingportion 88 are permanently joined by the permanent adhesive 34 whenpresent, or by the pressure-sensitive adhesive when it is appliedeverywhere between the structures.

The first score line 52 includes the interrupted areas 57 and transversescore lines 58 as previously described. Prior to initial opening of thepackage, the uncut condition of the interrupted areas 57 is readilyapparent, such that the consumer can see that the package has not yetbeen opened.

When the outer opening portion 86 is detached from the outer wrapperalong the first score line 52 and is peeled back as in FIG. 5, the outerlayer of the wrapper tears through the interrupted areas 57. The inneropening portion 88 remains affixed to the outer opening portion andcomes with it, thereby creating an opening 94 in the top surface of theouter wrapper 74 as defined by the second score line 62. The outer andinner opening portions essentially form a flap that remains attachedalong a hinge line defined between the free ends of the two legs of theU-shaped score lines.

The package is reclosable by re-attaching the pressure-sensitiveadhesive 20 to the surface 92 of the inner structure 42 to restore thepackage to a closed condition as shown in FIG. 6. It will, however, bereadily apparent that the package has already been opened, because thefilm will be torn through the tear portions 65. No amount of care inreplacing the flap in its original position can erase the fact that theinterrupted areas have been torn through. Accordingly, the inventionprovides a reliable tamper-evidence feature that is not easilycircumvented. Furthermore, in some embodiments, the outer structure 10can be substantially non-transparent or opaque without compromising thefunctionality of the tamper-evidence feature; this is in contrast tosome prior-art structures in which the outer structure must betransparent because the tamper-evidence feature is formed in the innerstructure and is covered by the outer structure. The non-transparent oropaque character of the outer structure 10 can be a characteristic ofthe film material itself, or can be achieved by a coating of ink or thelike on the film.

The outer structure 10 preferably has a greater affinity for bondingwith the pressure-sensitive adhesive 20 than does the surface 92 of theinner structure 42, and hence the pressure-sensitive adhesive 20 isdetached from the surface 92 and remains attached to the marginal region90 of the outer opening portion 86 as shown in FIGS. 5 and 7. Thegreater bonding affinity of the outer structure 10 can be achieved invarious ways. When the outer structure comprises a layer of PET and thelayer 82 of the inner structure to which the pressure-sensitive adhesiveis attached comprises a polyolefin such as polypropylene, orientedpolypropylene, or metallized oriented polypropylene, the PET willnaturally have a greater affinity for bonding to the adhesive than willthe polyolefin layer. Additionally or alternatively, the surface of theouter structure 10 can be treated, as previously noted, by coronadischarge or flame treatment, to increase the surface energy and enhancethe bonding affinity. It is also possible, as already noted, to controlthe bond strength of the pressure-sensitive adhesive to the layer 82 byincluding an additive in the adhesive to reduce the bond strength, ifdesired.

Although it is preferred to have the pressure-sensitive adhesive beapplied to the outer structure and to remain on the outer structure uponopening, it is also within the scope of the invention to apply thepressure-sensitive adhesive to the inner structure and to remain on theinner structure upon opening. This is less preferred, however, becauseof the greater tendency for crumbs or the like from the containedproducts to become adhered to the pressure-sensitive adhesive andthereby reduce its adhesiveness with repeated openings and reclosings.It is believed that this tendency is reduced when the pressure-sensitiveadhesive remains with the outer structure, since it is out of the way ofthe package opening when products are being removed.

It will be appreciated from the above description that laminates made inaccordance with the invention provide a tamper-evidence function for apackage because after opening it is impossible to replace the openingportions 86, 88 in such a way as to completely restore the package toits original unopened condition, as previously noted. When printing isincluded on the laminate, it is even more noticeable when the packagehas been opened because it is difficult to achieve perfect registrationof the printed matter across the score line when reclosing the package.

The printing on the laminate can include text adjacent to theinterrupted areas 57 of the first score line 52, calling the consumer'sattention to the presence of the interrupted areas and indicating thatif they are torn through at a tear portion 65, the consumer should notpurchase the package.

The laminates made in accordance with the invention can be used forforming other types of packages or tamper-evidence features. Forinstance, FIG. 8 shows a stand-up pouch 100 constructed from thelaminate 46 as described above. The first score line 52 and second scoreline 62 are formed in a side wall of the pouch. The opening/reclose andtamper-evidence features operate in a manner similar to that describedabove. An alternative form of a thumb “tab,” 25 is included, wherein acorner portion of the outer flap defined by the first score line 52 isleft free of pressure-sensitive adhesive 20.

The packages illustrated in FIGS. 9, 10 and 11 show other stand-uppouches 100 with alternative types of tamper-evidence features. Inparticular, the stand-up pouch 100 of FIG. 9 includes a tab 25 thatextends from an edge of outer portion 86. Preferably, tab 25 is definedby first score line 52 and is free from pressure sensitive adhesive 20or lamination to the second structure 42. The end of the tab 25 is thenattached or anchored to a portion of the outer layer 74 or along thetransverse seal line 76. The tab 25 illustrated in FIG. 9 may alsoinclude an indentation 55 between the outer portion 86 and where the endof tab 25 is attached to the stand-up pouch 100. By forming the tab 25in this way, a user may easily access an underside of the tab 25 with afinger and open the stand-up pouch 100 by pulling the tab generallyalong the downstream direction (generally top-to-bottom in FIGS. 8-10).By pulling on the tab 25 in this way, the tab 25 will tear at or nearthe indentation 55, or tear portion 65, and allow the stand-up pouch 100to open. Thus, the stand-up pouch 100 cannot be opened withoutintroducing a tear into the tab 25 thereby creating a tamper-evidencefeature that is clearly visible.

The stand-up pouch 100 of FIGS. 10 and 11 show other embodiments of tab25 with a tamper-evidence feature. In FIG. 10, tab 25 also is defined byfirst score line 52 and extends from an edge of outer portion 86. Theend of the tab 25 is attached or anchored to a portion of the outerlayer 74 or along the transverse seal line 76 and is free from pressuresensitive adhesive 20 or lamination to the second structure 42. The tab25 in FIG. 10 includes a prong 59 extending from a side of the tab 25between the outer portion 86 and where the end of tab 25 is attached tothe stand-up pouch 100. The presence of prong 59 facilitates the task ofa user tearing through a portion of the tab 25 at a tear portion 65before opening the stand-up pouch 100 by providing a surface that iseasily grasped.

The embodiment in FIG. 11 includes two tabs 25 that include tearportions 65 in addition to a thumb tab 23. Both tabs 23 and 25 also aredefined by first score line 52 and extend from an edge of outer portion86 and are free from pressure sensitive adhesive 20 or lamination to thesecond structure 42. The end of tabs 25 are attached or anchored to aportion of the outer layer 74 or along the transverse seal line 76. Inuse, tab 23 may be used to open the pouch 100 and to assist in tearingthrough tear portions 65 of tabs 25.

It should be noted that the terms “line of weakness” and “score line” asused herein refer either to a complete cutting through the thickness ofone or more layers of the laminate or to a partial cutting through ofthe thickness of such layer(s) allowing the layer(s) to be severed alongthe score line.

The packages described above are formed by completely enveloping thecontents in the flexible laminate. Alternatively, however, it is withinthe scope of the invention to employ the flexible laminate as a liddingstock for forming flexible lids that can be secured (e.g., byheat-sealing or the like) to a flange of a tray or other container thatcontains the contents. In this manner, the lid includes a built-inopening and reclose feature as previously described. For instance, FIG.12 shows a package 110 comprising a container body 112 having a sidewall 114 and a flange 116 extending from the upper edge of the sidewall. The container body 112 can comprise various materials (e.g.,polymer, paper, foil, etc.) and can be formed by various methods (e.g.,thermoforming, molding, etc.). The open top of the container body isclosed by a lid 118 formed of a flexible laminate 46 in accordance withthe invention. The lid is sealed to the flange 116 by any suitabletechnique, such that the lid is firmly attached to the flange. The lidincludes an opening/reclose feature formed by a first score line 52 anda second score line 62 and pressure-sensitive adhesive 20, and atamper-evidence feature as previously described. The package 110 alsoincludes a thumb “tab” 25 generally as described in connection with FIG.8; alternatively, a thumb tab of the type shown in FIGS. 4 and 5 can beused.

Many modifications and other embodiments of the inventions set forthherein will come to mind to one skilled in the art to which theseinventions pertain having the benefit of the teachings presented in theforegoing descriptions and the associated drawings. Therefore, it is tobe understood that the inventions are not to be limited to the specificembodiments disclosed and that modifications and other embodiments areintended to be included within the scope of the appended claims.Although specific terms are employed herein, they are used in a genericand descriptive sense only and not for purposes of limitation.

What is claimed is:
 1. A flexible packaging structure having built-inopening/reclose and tamper-evidence features, comprising: an outerstructure adhesively joined in face-to-face relation to an innerstructure, the outer structure comprising a first flexible material andthe inner structure comprising a second flexible material; an outer lineof weakness formed in the outer structure, the outer line of weaknessdefining an outer opening portion that is separable from the outerstructure along the outer line of weakness; an inner line of weaknessformed in the inner structure, the inner line of weakness defining aninner opening portion that is separable from the inner structure alongthe inner line of weakness; wherein the inner opening portion is joinedto the outer opening portion such that lifting the outer opening portionout of the plane of the flexible packaging structure causes the inneropening portion to be lifted along with the outer opening portion so asto create an opening through the flexible packaging structure; wherein amarginal region of the outer opening portion is defined between theinner and outer lines of weakness, the marginal region overlying anunderlying surface of the inner structure; wherein a pressure-sensitiveadhesive is disposed on one of an overlying surface of the outer openingportion and the underlying surface of the inner structure forre-adhering the overlying surface to the underlying surface afteropening; and a tamper-evidence feature that is initially in an untorncondition prior to initial creation of the opening, and whose untorncondition is apparent from a visual inspection of the outer structure,wherein the tamper-evidence feature comprises: a tab having a first endintegrally joined to an outer edge of the marginal region and anopposite second end anchored to a portion of the outer structure spacedfrom the outer edge, and at least one indentation extending into atleast one side of the tab, between the first and second ends of the tab,the tab being configured to be torn through.
 2. The flexible packagingstructure of claim 1, wherein the tab is free from pressure-sensitiveadhesive or lamination to the inner structure in at least the locationof the at least one indentation.
 3. The flexible packaging structure ofclaim 1, wherein the indentation is shaped and sized such that a usermay use a finger to access an underside of the tab via the indentationand pull the tab to tear through the tab.
 4. The flexible packagingstructure of claim 1, wherein the tab is configured to be torn throughbetween the first and second ends of the tab.
 5. The flexible packagingstructure of claim 1, wherein the tab is configured to be torn throughin the location of the at least one indentation.
 6. The flexiblepackaging structure of claim 1 comprising two indentations.
 7. Theflexible packaging structure of claim 6, wherein the two indentationsare located on opposite sides of the tab.
 8. The flexible packagingstructure of claim 1, wherein the outer structure is coextensive withthe inner structure.
 9. The flexible packaging structure of claim 1,wherein the inner structure includes a layer of heat-sealable materialforming an inner surface of the flexible packaging structure.
 10. Theflexible packaging structure of claim 1, wherein the inner structureincludes a barrier layer providing a barrier against passage of at leastone of moisture and oxygen.
 11. The flexible packaging structure ofclaim 10, wherein the barrier layer comprises a polymer film having acoating of vapor-deposited metal.
 12. The flexible packaging structureof claim 11, wherein the outer structure comprises a layer ofpolyethylene terephthalate, and the inner structure comprises amulti-layer web comprising a metallized film and a sealant layer. 13.The flexible packaging structure of claim 12, wherein the metallizedfilm comprises metallized oriented polypropylene.
 14. A flexiblepackaging structure, comprising: a flexible packaging laminatecomprising an outer structure adhesively laminated to an innerstructure; an opening and reclose feature formed in the laminate, andcomprising an outer flap portion formed by scoring through the outerstructure along an outer score line, and an inner flap portion formed byscoring through the inner structure along an inner score line, the innerscore line creating an opening into the container when the flap portionsare peeled back in a first direction, a marginal region of the outerflap portion extending beyond an edge of the inner flap portion andoverlying an underlying surface of the inner structure, both portionsbeing peeled back as a unit upon opening of the container; and atamper-evidence feature that is initially in an untorn condition priorto initial creation of the opening, and whose untorn condition isapparent from a visual inspection of the outer structure, wherein thetamper-evidence feature comprises a tab having a first end integrallyjoined to an outer edge of the marginal region and an opposite secondend anchored to a portion of the outer structure spaced from the outeredge, at least one indentation extending into at least one side of thetab, between the first and second ends of the tab, the tab beingconfigured to be torn through.
 15. The flexible packaging structure ofclaim 14, wherein the tab is free from pressure-sensitive adhesive orlamination to the inner structure in the location of the at least oneindentation.
 16. The flexible packaging structure of claim 14, whereinthe indentation is shaped and sized such that an underside of the tab isaccessible and once accessed, the tab can be pulled away from the firstend of the tab, the second end of the tab, or both, to tear through thetab.
 17. The flexible packaging structure of claim 14, wherein the tabis configured to be torn through between the first and second ends ofthe tab.
 18. The flexible packaging structure of claim 14, wherein thetab is configured to be torn through in the location of the at least oneindentation.
 19. The flexible packaging structure of claim 14 comprisingtwo indentations.
 20. The flexible packaging structure of claim 19,wherein the two indentations are located on opposite sides of the tab.